[lincpimp]

Amp rating is based on c rating and mah capacity.

Usually the battery is rated at continuous and burst, continuous is what you should focus on.

Take the mah (milliamp hours) of the battery and divide by 1000 to get ah (amp hours).

Then multiply the ah by the c rating and you have the amp output.

So say we have a 5000mah 20c continuous lipo. 5000/1000=5, 5x20=100amps.

This gets you close, and always factor a 20-25% margin. So if you think you need 80amps, use at least a 100amp capable lipo.